A device of this type is known from the KR 10 2014 00 55 653 A. In this known arrangement, a simple plate is provided as the carrier, from which a vertical pin with laterally projecting guide rails protrudes, onto which an actuating member provided with a corresponding recess and blocked in the direction of rotation by the guide rails is slidable in the axial direction, which is provided with an external thread and co-operates therewith with a threaded bushing, which surrounds it and is provided with an internal thread, which is connected via a circumferential freewheel coupling to a winding drum which surrounds it, on which the drawstring elements engage and which co-operates with a blocking device. This well-known arrangement requires a high construction effort and leads to a large construction height.
U.S. Pat. No. 7,721,468 B1 discloses a further device for drawstring actuation, in which a housing acting as a carrier and insertable into a recess in the sole of the shoe is provided, in which a vertical bearing pin extending between the housing, base and cover is provided, on which a disc pack with a winding disc for the drawstring elements and a drive disc arranged thereabove for receiving a drive cable is received in an axially rotatable manner. The winding disc on which the drawstring elements engage is provided on its lower and upper sides with wedge-shaped ratchet elements which, on the one hand, cooperate with ratchet elements provided on the bottom side and, on the other hand, with ratchet elements provided on the underside of the drive disc in opposite directions, in each case locking in one direction and not locking in the other direction. This well-known arrangement also requires a great deal of construction work as a result of the ratchet elements required and leads to a comparatively large overall height as a result of the axial movement of the disc pack. The discs of the disc pack are mounted on the assigned bearing pin only in the radial direction. An axial bearing is not possible due to the axial mobility.
Another device for drawstring actuation is known from US 2005/01 98767 A. The carrier is an annular body embedded in the sole of the shoe, which provides an open space at the top and bottom for the winding disc, the storage of which is therefore difficult. In the known arrangement, the winding disc and the actuating member in screw engagement therewith are each connected to a pawl wheel in which an associated pawl engages, allowing rotation in only one direction. When the actuating member is pressed down, it is blocked in such a way that a rotation of the winding disc, which is in screw engagement with it, is induced and vice versa. The rotation of the winding disc only takes place against the pull of the drawstring elements.
No return spring is provided which engages or interacts with the winding disc and/or the actuating member. It is therefore difficult to return the winding disc and the actuating member to their initial position. In the known arrangement, a return spring is provided. However, the latter is located between the carrier embedded in the sole and a flap pivotally attached thereto and formed by the rear portion of an insole and serves only to establish a latent state of equilibrium between the force exerted by the wearer of the shoe and the force transmitted by the drawstring elements. This well-known arrangement also has a comparatively complicated structure and is not functionally safe and reliable enough.